Manager Forum

We have a 2002 dodge truck with a 5.9L in it and it first came in last winter not running and found the ecu had gone bad.

So had it taken to a Dodge dealer for that then it came back 6-2011 not running and found then the coil was out. Then 7-2011 same thing and now it is back again with a bad coil. We are not using the cheap ones ether.

So was hoping then someone out there has seen this before? And the truck had a full tuneup by another shop before it ever came here.

First thing that comes to my mind is voltage at the coil. That has got to be within .1 volt the same as the battery. Low voltage will take out a coil fast.

Ok will check that after lunch thanks

If you're not using a factory OEM coil, now would be a good time to start. Expensive or not, the aftermarket is awful these days. I've personally done several coils on a vehicle until I went OEM.

After a coil, I'd check the primary waveform real close. Also powers and grounds real close.

Well, you mention the difference between oem and aftermarket parts. On ignition coils, I have not seen any major issue of any kind however I do agree that on sensors and computer parts I strictly use oem. I have physically tested coils already both with dvom and lab scope and have not seen any issues. However, some guys will swear there is a difference. Also, if there is excessive load on the minus side of the coil that can also affect coil durability.

It is a oem ecm and they put it in since it has to be flashed. Checked and i got a good ground at the coil have not checked power yet since i need to crank it at the same time.

i would carefully inspect the wiring going to the coil. if it's compromised at all, even if the wire has been pierced, it will cause a voltage or connection issue and that will cause a melt down.

Well, in looking at a wiring diagram, I see that the power supply is also shared with the 8 fuel injectors as well as the auto shut down relay. I have to wonder if the amperage to the ignition coil is a bit low due to excessive draw from something else. I have seen this in the past.

Just a thought.

an easy way to ck. amp. is by using a headlamp bulb. you very well may have the voltage applied but if there is no amp. it will damage the coil. i would use it in line on both the pwr and grd side and see if the brightness is equal to the load. grd side go from the batt. threw the headlamp straight to the grd.circut of the coil it should be nice and bright. good luck hope you find something.